The invention relates to improvements in hydrokinetic torque converters of the type often employed in the power trains of motor vehicles. More particularly, the invention relates to improvements in hydrokinetic or hydrodynamic torque converters of the type wherein a rotary housing normally confines a pump, a turbine, a stator (if necessary), and a suitable lockup clutch or bypass clutch. The pump can receive torque from a prime mover (such as the combustion engine of a motor vehicle), for examples by way of the housing, and the turbine can drive a rotary part, e.g., the input shaft of a transmission in a motor vehicle. It is also known to equip a hydrokinetic torque converter with a torsional vibration damper which is installed in the path of transmission of torque between the input and output members of the torque converter. As a rule, the turbine is installed in the housing between the pump and a wall of the housing, normally a wall confronting the output element of the prime mover and being disposed between such output element and the turbine, as seen in the axial direction of the housing.. The lockup clutch is engageable and disengageable in response to a change of fluid pressure in a compartment which is provided in the housing between the turbine and a wall of the housing.
Published German patent application No. 44 20 959 discloses a hydrokinetic torque converter employing a lockup clutch wherein a friction lining is applied to a piston which is movable relative to the turbine in the axial direction of the pump. For example, the lockup clutch can employ an annular piston.
A drawback of the just outlined torque converters is that the utilization of a piston which is movable in the housing in the axial direction of the turbine and pump renders it necessary to increase the space requirements of the torque converter accordingly (as seen in the axial direction of the pump and turbine) This is in contrast with the trend toward larger and more powerful engines and toward larger transmissions, i.e., it is desirable to reduce the space requirements of the power train between the engine and the transmission to a minimum.